| Full text | |
| Author(s): |
Batista, Jr., Joao M.
[1]
;
Batista, Andrea N. L.
[1]
;
Kato, Massuo J.
[2]
;
Bolzani, Vanderlan S.
[1]
;
Lopez, Silvia N.
[3]
;
Nafie, Laurence A.
[4]
;
Furlan, Maysa
[1]
Total Authors: 7
|
| Affiliation: | [1] Univ Estadual Paulista UNESP, Inst Quim, Dept Quim Organ, BR-14800900 Araraquara, SP - Brazil
[2] Univ Sao Paulo, Inst Quim, BR-05508900 Sao Paulo - Brazil
[3] Univ Nacl Rosario, Fac Ciencias Bioquim & Farmaceut, RA-2000 Rosario - Argentina
[4] Syracuse Univ, Dept Chem, Syracuse, NY 13244 - USA
Total Affiliations: 4
|
| Document type: | Journal article |
| Source: | Tetrahedron Letters; v. 53, n. 45, p. 6051-6054, NOV 7 2012. |
| Web of Science Citations: | 14 |
| Abstract | |
A reinvestigation of the monoterpene chromane ester enriched fraction from Peperomia obtusifolia using chiral chromatography led to the identification of a minor peak, which was elucidated by NMR and HRMS as fenchyl-3,4-dihydro-5-hydroxy-2,7-dimethyl-8-(3 `'-methyl-2 `'-butenyl)-2-(4'-methyl-1',3'-pentadienyl)-2H-1-benzopyran-6-carboxylat e, the same structure assigned to two other fenchyl esters described previously, pointing out a stereoisomeric relationship among them. Further NMR analysis revealed that it was actually a mixture of two compounds, whose absolute configurations were determined by VCD measurements. Although, almost no vibrational transitions could be assigned to the chiral chromane, the experimental VCD spectrum was largely opposite to that obtained for the average experimental VCD {[}(2S,1'''R,2'''R,4'''S + 2R,1'''R,2'''R,4'''S)/2] for fenchol derivatives. These results allowed us to assign the putative compounds as a racemic mixture of the chiral chromane esterified with the monoterpene (1S,2S,4R)fenchol, which had not been identified in our early work. (C) 2012 Elsevier Ltd. All rights reserved. (AU) | |